The subject matter of this disclosure relates generally to common mode chokes, and more particularly, to a three-phase common mode choke structure suitable for use in high power applications.
Three-phase common mode chokes may be used as a common mode filter in medium voltage (MV) large power rating drives. Such common mode chokes may be a key component for an MV drive without a transformer.
Ferrite ring cores are generally no longer a suitable core for common mode chokes as transmission power levels continue to increase. These increasing transmission power levels may influence the use of core and winding materials, and may necessitate the use of core and winding materials more suitable for high power magnetic devices.
Further, a special winding arrangement may be required for a multi-phase choke such as a three-phase common mode choke when used at certain high transmission power levels. The absence of such special winding arrangements may otherwise cause extreme overheating, or result in undesirably strong unbalanced differential mode inductance between different phases.
In view of the foregoing, there is a need for a multi-phase common mode choke such as a three-phase common mode choke that is suitable for use with high power transmission applications and that substantially controls and balances differential mode inductance between different phases of the common mode choke to reduce or eliminate system asymmetry.